Conjugate Addition of Organometallic Reagents to Acyclic Dienones
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90% ee; anal. calcd. for C19H20O: C 86.32, H 7.63; found: C
86.30, H 7.62.
2H), 3.68 (m, 1H), 6.61 (d, J=16.1 Hz, 1H), 7.07–7.57 (m,
8H), 7.87 (d, J=16.1 Hz, 1H); 13C NMR (50 MHz, CDCl3):
d=20.2, 20.7, 33.2, 43.9, 126.7, 127.0, 127.3, 127.5, 128.3,
128.6, 129.7, 130.1, 131.1, 132.8, 135.2, 138.2, 141.1, 198.9;
MS (CI): calcd. for C20H21Cl2O (MH+): 347, found 347;
(S)-E-1,5-Diphenylhex-1-en-3-one (2b): The crude prod-
uct was purified by flash chromatography (heptane/
AcOEt=97:3) to give pure 2b as a white solid, mp 66–688C.
1H NMR (300 MHz, CDCl3): d=1.33 (d, J=7.0 Hz, 3H),
2.85–3.03 (m, 2H), 3.43 (q, J=7.3 Hz, 1H), 6.69 (d, J=
16.1 Hz, 1H), 7.18–7.53 (m, 11H); 13C NMR (50 MHz,
CDCl3): d=21.8, 35.8, 49.3, 126.3, 126.4, 126.8, 128.2, 128.5,
128.9, 130.4, 134.5, 142.6, 146.4, 199.1; HR-MS: calcd. for
C18H18O: 250.1358, found: 250.1368; HPLC on Chiralpak
+
calcd. for (M+NH4 ): 364, found: 364; (it was not possible
to obtain an exact mass); HPLC on Chiralpak AD column
(heptane/propan-2-ol=96:4,
flow=1.0 mLminꢀ1):
tR
6.59 min (minor), tR 6.99 min (major); [a]D: ꢀ6.2 (c 0.50,
CHCl3), 34% ee.
(S)-E-1,5-Bis-(3-bromophenyl)-hept-1-en-3-one (2g): The
crude product was purified by flash chromatography (hep-
tane/AcOEt=97:3!95:5) to give pure 2g in 66% yield as a
colorless oil. 1H NMR (300 MHz, CDCl3): d=0.81 (t, J=
7.3 Hz, 3H), 1.60–1.74 (m, 2H), 2.93 (d, J=7.0 Hz, 2H),
3.11 (m, 1H), 6.63 (d, J=16.1 Hz, 1H), 7.15–7.64 (m, 9H);
13C NMR (100 MHz, CDCl3): d=12.0, 29.1, 42.8, 47.9, 123.0,
126.5, 126.9, 127.3, 127.9, 129.5, 130.0, 130.4, 130.5, 130.8,
133.2, 136.5, 140.8, 146.9, 198.2; HR-MS: calcd. for
C19H18Br2O: 419.9724, found: 419.9755; HPLC on Chiralcel
AD
column
(heptane/propan-2-ol=96:4,
flow=
1.0 mLminꢀ1): tR 7.52 min (minor), tR 8.37 min (major);
[a]D: +20.5 (c 0.20, CHCl3), 95% ee.
(S)-E-1,5-Diphenyl-6-methylhept-1-en-3-one (2c): The
crude product, obtained by the general procedure, was puri-
fied by flash chromatography (heptane/AcOEt=97:3) to
give pure 2c in 60% yield as a white solid, mp 97–988C
1
(lit.[15] m p 958C). H NMR (300 MHz, CDCl3): d=0.80 (d,
J=6.6 Hz, 3H), 1.00 (d, J=6.6 Hz, 3H), 1.93 (m, 1H), 3.07
(m, 3H), 6.64 (d, J=16.1 Hz, 1H), 7.16–7.50 (m, 11H);
13C NMR (100 MHz, CDCl3): d=20.3, 20.9, 33.3, 45.1, 48.2,
126.2, 126.3, 128.1, 128.2, 128.3, 128.9, 130.3, 134.5, 142.2,
143.4, 226.3; HR-MS: calcd. for C20H22O: 278.1671, found:
278.1673; HPLC on Chiralpak AD column (heptane/
OD
column
(heptane/propan-2-ol=99:1,
flow=
1.0 mLminꢀ1): tR 23.0 min (minor), tR 26.0 min (major);
[a]D: +3.1 (c 0.32, CHCl3), 90% ee.
(S)-E-1,5-Bis-(3-methylphenyl)-hept-1-en-3-one (2h): The
crude product was purified by flash chromatography (hep-
tane/AcOEt=97:3!95:5) to give pure 2h in 69% yield as a
colorless oil. 1H NMR (300 MHz, CDCl3): d=0.80 (t, J=
7.3 Hz, 3H), 1.59–1.77 (m, 2H), 2.33 (s, 3H), 2.36 (s, 3H),
2.93 (d, J=7.0 Hz, 2H), 3.11 (m, 1H), 6.64 (d, J=16.5 Hz,
1H), 6.99–7.30 (m, 8H), 7.44 (d, J=16.1 Hz, 1H); 13C NMR
(75 MHz, CDCl3): d=12.1, 21.3, 21.5, 29.1, 43.2, 48.0, 124.6,
125.4, 126.3, 127.0, 128.2, 128.4, 128.7, 128.8, 131.2, 134.4,
137.8, 138.5, 142.6, 144.5, 199.4; HR-MS: calcd. for C21H24O:
292.1827, found: 292.1823; HPLC on Chiralpak AD column
propan-2-ol=96:4,
flow=1.0 mLminꢀ1):
tR
7.76 min
(minor), tR 8.66 min (major); [a]D: +13.2 (c 0.50, CHCl3),
73% ee.
(S)-E-1,5-Diphenylnon-1-en-3-one (2d): The crude prod-
uct was purified by flash chromatography (heptane/
AcOEt=97:3) to give pure 2d in 61% yield as a white solid,
mp 89–908C. 1H NMR (400 MHz, CDCl3): d=0.83 (t, J=
7.0 Hz, 3H), 1.10–1.31 (m, 4H), 1.62–1.71 (m, 2H), 2.94 (dd,
J=7.0, 2.9 Hz, 2H), 3.23 (m, 1H), 6.64 (d, J=16.1 Hz, 1H),
7.18–7.50 (m, 11H); 13C NMR (100 MHz, CDCl3): d=14.0,
22.6, 29.7, 36.0, 41.6, 48.4, 126.3, 126.5, 127.6, 128.2, 128.4,
128.9, 130.4, 134.5, 142.5, 144.8, 199.3; anal. calcd. for
C21H24O (292.4): C 86.26, H 8.27; found: C 85.90, H 8.30;
HR-MS calcd. for C21H24O: 292.1827, found: 292.1819;
HPLC on Chiralpak AD column (heptane/propan-2-ol=
96:4, flow=1.0 mLminꢀ1): tR 6.88 min (minor), tR 7.55 min
(major); [a]D: +15.7 (c 0.37, CHCl3), 89% ee; anal. calcd
for C21H24O: C 86.26, H 8.27; found: C 85.90, H 8.30.
(S)-E-1,5-Bis-(2-chlorophenyl)-hept-1-en-3-one (2e): The
crude product was purified by flash chromatography (hep-
tane/AcOEt=97:3) to give pure 2e in 76% yield as a color-
(heptane/propan-2-ol=98:2,
flow=1.0 mLminꢀ1):
tR
7.50 min (minor), tR 7.98 min (major); [a]D: +31.3 (c 0.61,
CHCl3), 88% ee.
(S)-E-1,5-Bis-(4-chlorophenyl)-hept-1-en-3-one (2i): The
crude product was purified by flash chromatography (hep-
tane/AcOEt=97:3) to give pure 2i in 71% yield as a white
1
solid, mp 76–778C. H NMR (300 MHz, CDCl3): d=0.80 (t,
J=7.3 Hz, 3H), 1.54–1.77 (m, 2H), 2.92 (d, J=7.3 Hz, 2H),
3.13 (m, 1H), 6.60 (d, J=16.1 Hz, 1H), 7.14 (d, J=8.1 Hz,
2H), 7.24–7.43 (m, 7H); 13C NMR (50 MHz, CDCl3): d=
12.0, 29.2, 42.5, 48.0, 126.6, 128.5, 129.0, 129.2, 129.4, 131.9,
132.9, 136.4, 141.1, 142.9, 198.5; anal. calcd. for C19H18Cl2O
(333.3): C 68.48, H 5.44; found: C 68.40, H 5.52; HR-MS:
calcd. for C19H18Cl2O: 332.0735, found: 332.0729; HPLC on
Chiralpak AD column (heptane/propan-2-ol=95:5, flow=
1.0 mLminꢀ1): tR 9.94 min (minor), tR 13.71 min (major);
[a]D: +33.9 (c 0.75, CHCl3), 95% ee; anal. calcd. for
C19H18Cl2O: C 68.48, H 5.44; found: C 68.40, H 5.51.
1
less oil. H NMR (300 MHz, CDCl3): d=0.84 (t, J=7.3 Hz,
3H), 1.77 (m, 2H), 3.00 (m, 2H), 3.80 (m, 1H), 6.66 (d, J=
16.1 Hz, 1H), 7.10–7.43 (m, 7H), 7.58 (m, 1H), 7.93 (d, J=
16.1 Hz, 1H); 13C NMR (75 MHz, CDCl3): d=11.8, 28.0,
39.0, 46.5, 127.0, 127.1, 127.4, 127.5, 127.9, 128.6, 129.7,
130.2, 131.1, 132.8, 134.3, 135.2, 138.4, 141.4, 198.6; MS (EI):
calcd. for C19H18Cl2O: 332, found: 332 (it was not possible to
obtain an exact mass); HPLC on Chiralpak AD column
(S)-E-1,5-Bis-(4-methoxyphenyl)-hept-1-en-3-one
(2j):
The crude product was purified by flash chromatography
(heptane/AcOEt=95:5!80:20) to give pure 2j in 59%
yield as a white solid, mp 84–868C. 1H NMR (300 MHz,
CDCl3): d=0.79 (t, J=7.3 Hz, 3H), 1.56–1.76 (m, 2H), 2.89
(d, J=7.0 Hz, 2H), 3.09 (m, 1H), 3.77 (s, 3H), 3.84 (s, 3H),
6.53 (d, J=16.1 Hz, 1H), 6.83 (d, J=8.8 Hz, 2H), 6.89 (d,
J=8.8 Hz, 2H), 7.13 (d, J=8.4 Hz, 2H), 7.42 (d, J=16.5 Hz,
1H), 7.44 (d, J=8.8 Hz, 2H); 13C NMR (50 MHz, CDCl3):
d=12.0, 29.3, 42.6, 48.1, 55.1, 55.3, 113.7, 114.3, 124.3, 127.1,
(heptane/propan-2-ol=97:3,
flow=1.0 mLminꢀ1):
tR
7.22 min (minor), tR 7.78 min (major); [a]D: +35.5 (c 0.80,
CHCl3), 78% ee.
(S)-E-1,5-Bis-(2-chlorophenyl)-6-methylhept-1-en-3-one
(2f): The crude product was purified by flash chromatogra-
phy (heptane/AcOEt=97:3) to give pure 2f in 53% yield as
1
a colorless oil. H NMR (400 MHz, CDCl3): d=0.84 (d, J=
6.6 Hz, 3H), 1.03 (d, J=6.6 Hz, 3H), 2.00 (m, 1H), 3.04 (m,
Adv. Synth. Catal. 2007, 349, 1931 – 1937
ꢀ 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
1935